This application describes the qualifications and experience of the maternal-fetal medicine faculty and research team at the University of Texas Southwestern (UT Southwestern) Medical Center and Parkland Hospital and the facilities and patient population available to carry out clinical protocols sponsored by the NICHD Maternal-Fetal Medicine Units (MFMU) Network. UT Southwestern's Division of Maternal-Fetal Medicine includes 12 full-time faculty physicians certified in maternal-fetal medicine. In 2004, there were 16,223 obstetrical patients delivered at Parkland Hospital and approximately 58% were high-risk. Pregnancy complications of particular interest to the MFMU Network, for example, preterm birth and preeclampsia, are well represented in the obstetrics population at Parkland Hospital. Indeed, for the past 10 years, UT Southwestern's MFMU Network center has frequently been the first or second leading recruiter for Network protocols. A computerized perinatal database for all births at Parkland Hospital, operational since1982, continues to be a centerpiece in our center's academic productivity as well as an important component of our center's successful participation in the MFMU Network. Our center recently led the implementation and completion of the fetal oximetry randomized trial (FOX) and has been active in all aspects of the MFMU Network. Importantly, the maternal-fetal medicine physicians at UT Southwestern are philosophically dedicated to rigorous controlled trials intended to objectively evaluate principles of obstetrical care consistent with the mission of the MFMU Network. The perinatal research team described has been actively involved with and committed to the MFMU Network for the past 10 years and seeks to continue this collaboration.